In this work, new integrated radiation dosimeters using polymer films were developed and their characteristics were tested by irradiation experiments. As the polymer films, we selected conducting polymers such as polypyrrole and polyaniline. The dosimeters we developed can measure radiation dose as change of electrical conductivity of the film. Its principle is based on radiation-induced doping. The dosimeter consists of a strip of an undoped-polyaniline and a source material of dopant gas. In radiation fields, the polyaniline film is doped with the dopant gas which is formed by radiolysis of the source material, and this radiation-induced doping results in an increase of its conductivity.Halogenated materials were used as the source material. The polyaniline dosimeters, using polyvinylchloride (PVC), brominated epoxy resin and benzene hexachloride as the source materials, showed drastic increase in conductivity of the polyaniline in proportion to dadiation dose. Especially in the poly
… Moreaniline-PVC powder system, the conductivity increased linearly with an increase of dose in the wide range of about 10 to 10^5 Gy, and the radiation-induced doping was found to proceed quantitatively in proportion to the dose. This linear relation is one of important characteristics required for an integrated radiation dosimeter. It is considered that the increase in conductivity can be expressed as a function of the dopant content absorbed on the polyaniline film, and the amount of dopant depends of the G-value of the dopant gas liberated from the source material, weight of the source material and integrated radiation dose. The measurable dose range can be controlled by optimizing these factors. This measurement method and our dosimeters are, therefore, very promising for measurement of an integrated radiation dose in wide ranges.ポリアニリンの電導度変化は、基本的には発生するドーパントの量の関数、すなわちドーパント源のG値、ならびに照射線量との関数になると考えられる。したがってドーパント源をうまく選択することによって、種々の線量域で使用可能な素子を調製できる可能性がある。我々は種々のハロゲン元素を含むドーパント源を用いて照射実験を行い、ポリ塩化ビニル(PVC)、臭素化エポキシ樹脂、ベンゼンヘキサクロリド、SF_6などをドーパント源とすると、ポリアニリンの電導度は大きな増加を示すことを確認した。特にポリアニリン-PVC粉末系では電導度変化が良い線量依存性(10〜10^5Gy)を示した。この系において、ドーパントの同定、G値の測定、ポリアニリン表面にドープされた塩素の定量等を行い、放射線誘起ド-ピングが線量に比例して定量的に進行し、放射線測定に極めて有効であることを確かめた。なお、本年度の成果の一部は国際学会等(Int.Sym.on Polymers for Microelectronics,PME'93 平成5年11月、他)で発表した。 Less